The same Pew study reports that about 50% of adults over the age of 18 get married; this number is compared to 72% in 1960." That's a big difference over time. They also find that "Pew Research Center findings show that most of the increase in nonmarital births occurs among couples living together." Many experts believe that cohabiting couples have a higher risk of instability than marriage. They even think you should get married before your child turns 3 to have a better chance of keeping the relationship together, even though this may have been the norm in previous generations. as with everything with time