An increasing number of U.S. couples shack up before they tie the knot.
Most women ages 30 or younger said they've lived with a partner outside of marriage (known as cohabiting) at some point in their lives, according to a new survey from the Centers for Disease Control and Prevention.
And just 23 percent of women now say they were married when they first lived with their partner, down from 30 percent in 2002, and 39 percent in 1995.
Here's what we know about cohabitation:
Cohabitation has become the norm in the United States. By age 30, about 75 percent of heterosexual women say they've cohabited at some point in their lives. And nearly half of women (48 percent) ages 15 to 44 say they were not married when they first lived with their partner, compared to 23 percent who were married, and 29 percent who were single.
People with more education and financial resources are more likely to view cohabiting as a "stepping stone" to marriage, while those with less education and fewer resources see cohabiting as an alternative to marriage, said Susan Brown, a professor of sociology at Bowling Green State University in Ohio.
For instance, in a new CDC report, 53 percent of cohabiting women with a bachelor's degree or higher got married over a three-year period, compared with 30 percent of those with less than a high school diploma.
Couples today often say they want to be financially secure, have a stable job and finished education before they enter marriage, which means they tend to delay marriage.
"The bar for marriage has risen in recent years," Brown said. (The average age for marriage in the United States is 26.5 for women and 28.5 for men — an all time high.) It's also become more acceptable to cohabit rather than marry, and cohabiters can obtain many of the benefits of marriage, Brown said.
While studies 20 or 30 years ago showed that cohabiting couples were more likely to get divorced once they got married, the most recent research suggests that there's no positive or negative effect of cohabitation on later marriage, Brown said. That is, cohabiting doesn’t put you at greater risk for getting a divorce, but it won't protect you from divorce either, Brown said.
Previously, cohabitation may have been limited to select couples who were more prone to divorce, but today, the outcome is different because cohabitation is much more common, Brown said.
A study published last year found that cohabiting couples were about as well off in terms of mental and physical health than married couples.
Most U.S. marriages now begin in cohabitation, said Corinne Reczek, an assistant professor in the department of sociology at the University of Cincinnati.
"Partners often cohabit as a trial marriage to ensure that their marital choice is appropriate, or in order to save money in order to marry," Reczeksaid.
Some research suggests that children of cohabiting couples don't fare as well in terms of their health and education than children of married couples. But increasingly, research shows that these disparities are due to unstable relationships and financial struggles that occur in among some cohabiters, rather than cohabiting per se, Reczek said.
"It is not cohabitation that is causing worse child outcomes, but the social conditions within which cohabitation takes place that may matter for child outcomes," Reczeksaid. "Bolstering the socioeconomic resources and residential stability of cohabiting unions is one way to ameliorate these potential negative effects."