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The national debate over same-sex marriage has obscured a different trend: cohabitation. Whether Americans are gay or straight, it is more popular than ever to live together, outside of marriage. NPR's Rob Stein reports.
ROB STEIN, BYLINE: The number of Americans who lived together before they get married, or instead of getting married, has been increasing for years. But Casey Copen of the National Center for Health Statistics, says it's never been quite like this.
CASEY COPEN: There are a greater percentage of people cohabitating today, than ever before. This is the highest rate of cohabitation that we have seen, to date.
STEIN: According to the latest results of a big government survey that's been tracking family dynamics for decades, almost half of those surveyed had lived with someone. And that's a big jump from previous years.
COPEN: And that's compared to 34 percent in 1995.
STEIN: And not only are more people living together...
COPEN: Cohabitations are longer now today, than they were decade ago. On average, they last about 22 months, compared with 13 months from 1995.
STEIN: And for the first time, the researchers took a look at how often babies are being born to couples living together, outside of marriage.
COPEN: We're showing, now, that 19 percent of women - so about 1 out of 5 - had a pregnancy leading to a live birth in a cohabiting union.
STEIN: And many of these couples aren't getting married, even if they have a child together.
COPEN: So more cohabitations, more pregnancies in those unions, but less marriage as a result of a pregnancy.
STEIN: Now, the new analysis didn't examine the reason for these trends. But Copen and others say there are probably a bunch of reasons. One, according to sociologist Andrew Cherlin of Johns Hopkins, is that living together is simply more socially acceptable.
ANDREW CHERLIN: In 1972, I went home to have dinner with my parents and told them about my girlfriend. And they asked where she was living and I said, with me. And they nearly had a heart attack. Today, when my daughter married a few years ago, I would have been shocked had she not lived with her boyfriend. That's the difference that we've seen in just a generation.
STEIN: And another factor is probably the economy.
CHERLIN: Marriage is now seen as something you don't do until everything else in your life is in good shape. It's kind of a capstone experience, the last brick put in place. And people don't think they should marry until they think they have prospects for decent jobs; they have a good relationship; things are in great shape. And so they put off marriage.
STEIN: That's especially true for people with less education. Now, Cherlin thinks all this worrisome, especially when it involves children.
CHERLIN: I think that what kids need are stable families. So far in the U.S., our cohabiting relationships have been short - which exposes the children in them, to lots of churning in their families.
STEIN: But others aren't so worried. Casey Copen - of the National Center for Health Statistics - notes that many cohabitating couples do end up getting married, or just live together unmarried for years.
COPEN: Most of the literature in this area doesn't show differences in children's outcomes based on whether or not their parents are married. It's really the instability. So divorce, breaking up - that's what affects children, not necessarily the type of union they're in.
STEIN: Cherlin agrees that's the most important thing. He notes that many couples in Europe live together for decades, and raise families, without ever getting married. The question he has is whether the United States is headed in that direction, too.
Rob Stein, NPR News.
(SOUNDBITE OF SONG, "LIVING IN SIN")
BON JOVI: (Singing) Call it living in sin. Is it you and me or just this world we live in? We're living on love, they say we're living in sin. Whoa, come on... Transcript provided by NPR, Copyright NPR.