Cohabitation in the United States is at an all-time high.

As a lifestyle, cohabitation has increased by more than 1,500 percent in the past half century. In 1960 nearly a half million unmarried couples lived together. Currently, the number is more than 7.5 million.

Experts attribute the rise of cohabitation to the sexual revolution, the wide availability of birth control and the tight economy—sharing the bills makes cohabitation attractive.

Some people in their 20s even see cohabitation as a means to preserve their health from sexual disease.

In a nationwide survey conducted in 2001 by the National Marriage Project, then at Rutgers and now at the University of Virginia, “nearly half of all the 20-year-olds interviewed agreed with the statement, ‘You would only marry someone if he or she agreed to live together with you first, so that you could find out whether you really get along.’” Additionally, a majority of survey participants believed that living together prior to marriage “was a good way to avoid divorce.”

Clinical psychologists are learning that experience shows otherwise, according to a recent New York Times article.

Researchers see negative outcomes to cohabitation, calling them “the cohabitation effect.”

Couples who move in together before marriage “tend to be less satisfied with their marriages” and are more likely to divorce than couples who do not, the Times reports. In the past, the risk for couples to divorce was assessed by religion, education or politics. Research now suggests that “some of the risks lie in cohabitation itself.”

Studies show that most couples do not necessarily plan to live together—it just happens. This means that an intimate relationship begins without commitment to go the distance.

Live-in partners often have different, even unspoken agendas. The same studies show that women view cohabitation as a step toward marriage. Yet, men see living together as a way to test a relationship or postpone commitment. Unsurprisingly, these different views often lead to negative consequences even when the relationship proceeds to marriage.

However, researchers discovered that men and women do agree that their standards are lower for a live-in partner than they are for a spouse. How can this shared view lead to a strong and successful marriage?

Researchers looking at hard data are admitting that there is a downside to cohabitation. But even they don’t recognize the fundamental reason that cohabitation is such a terrible mistake.

The real reason cohabitation fails is that it breaks God’s law, which always brings negative consequences. These studies are simply proving that God’s law is a living law, and we ignore it at our peril.

There is an upside to marriage. Herbert W. Armstrong’s Why Marriage! Soon Obsolete? and The Missing Dimension in Sex give you the details on how to build a lasting and successful marriage without the need for cohabitation.