FOXSexpert: The Pros and Cons of 'Living in Sin'

Goldie Hawn and Kurt Russell do it. So do Susan Sarandon and Tim Robbins.

And these days, it's not just the celebrities. More and more unmarried couples are living together, and research indicates that most people have tried it.

The distinction between cohabitation and marriage is eroding in many contemporary societies. For years now, the number of couples choosing to live together without getting married has steadily increased.

Like it or not, cohabitation is here to stay; up to two-thirds of American households began as "starter marriages."

But is it smart to move in together when you aren't married?

There are pros and cons to this arrangement.

"Living in sin" is not a new idea. According to Stephanie Coontz, author of "Marriage, a History: How Love Conquered Marriage," the only difference between cohabitation and legal marriage in ancient Rome was the partners' intent.

For more than 1,000 years, the Roman Catholic Church recognized commitment by simply taking the couple's word. If a man and woman had privately agreed to marry, then they were seen as a married couple. Many modern-day thinkers have felt the same way. American anthropologist George Peter Murdock once defined marriage as "a global institution involving a couple cohabitating, engaging in sexual activity, and cooperating economically." For many couples, the actual act of officially tying the knot is just a technicality.

I can already hear the natives getting restless on this matter, ready to blast me on our blog. Just as with my previous examination of casual sex, I will likely be attacked for promoting an agenda meant to corrupt society.

As a sex educator, I have always strived to give people the facts so that they can make their own sexual decisions based on their own value system. Unlike many of my critics, I'm not here to moralize or judge.

I am originally from a country (Iceland) where we don't tell other people what they can do in their own bedroom. When I moved from Iceland to the U.S. in the 1980s, I was surprised to learn that, in America's eyes, my Icelandic countrymen – and family members – were basically regarded as a bunch of heathens because they have no problem with the concepts of "living in sin," or having children out-of-wedlock.

But in the decades since I experienced this culture shock, the acceptance of unmarried cohabitation, as well as children out-of-wedlock, has steadily grown in North America and Western Europe.

Cohabitation has been mainstreamed, especially with the help of Hollywood stars like Sarandon, Robbins, Hawn and Russell, who have publicly advocated their type of union.

What straw broke the camel's back? Surveys from the late 1950s through the 1970s reveal that there was a huge drop in support for conformity around issues like marriage.

People were more interested in self-fulfillment, intimacy, fairness and emotional gratification. They believed in autonomy and voluntary cooperation versus the obedience, authority and social expectations that have been traditionally expected of marriage.

Fast-forward to the 1990s, and we see an ever-increasing rate of cohabitation among both heterosexual and same-sex couples. Even elderly couples became part of the "shacking up" trend.

Cohabitation appeals to young and old for a number of reasons, including:

— It's great for those turned off by casual sex and who want a committed relationship, but do not feel ready to get married

— It offers financial benefits (for example, the pooling of incomes, and avoidance of paying higher income taxes)

— It provides companionship.

— It's a way to test compatibility before tying the knot.

— For same-sex couples who are banned from getting married, it may be the only option.

— In some states and countries, cohabitation is regarded as common-law marriage if you have lived together for a certain amount of time and have a child.

— It promises a more even split of the housework than that carried out by married couples.

Cohabitation is also attractive to those who don't want their commitment to be matter of legal record. Some people have philosophical objections to involving government – or religion — in their affairs. It can also help couples in guarding their money; for example, single seniors could lose their economic benefits if they remarry. Not marrying further prevents any disagreements that can spring up around inheritance arrangements if lovers have grown children from previous relationships. Finally, some people just don't see a need to get hitched.

But some harsh realities need to be acknowledged for those who choose not to go the "'till death do you part" route.

— In the U.S. and Great Britain, the divorce rate is slightly higher among those who cohabitated before marriage than for couples who didn't. (Interestingly, this is not the case in France or Germany.)

— Data show that those who cohabitate are more likely, on average, to experience infidelity and domestic violence than married couples.

— In general, married couples in Western Europe and North America are happier, healthier, and better protected against economic setbacks and psychological depression than those in other living arrangements. It must be pointed out, however, that individuals in unhappy marriages are more psychologically distressed than the unmarried and do not have same health benefits, especially if you're the woman in the relationship.

— Finally, in societies around the world, marriage is regarded as the highest expression of commitment. And with that come much clearer rules as to the expectations of responsibility, intimacy and fidelity involved. With a marriage, you don't run the risk of a union being treated as something temporary or makeshift.

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Dr. Yvonne Kristín Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hand Guide to Your Orgasmic Hot Spots."

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