Even more couples are choosing to live together before they get married, according to a new report from the Centers for Disease Control and Prevention.

Between 2006 and 2010, nearly half of heterosexual women (48 percent) ages 15 to 44 said they were not married to their spouse or partner when they first lived with them, the report says. That's up from 43 percent in 2002, and 34 percent in 1995.

Just 23 percent of women in the new report said they were married when they first lived with their partner, down from 30 percent in 2002, and 39 percent in 1995.

And nearly 75 percent of women ages 30 or younger said they've lived with a partner outside of marriage (known as cohabiting) at some point in their lives, compared to 70 percent in 2002, and 62 percent in 1995, the report says.

The trend “reflects the fact that marriage is increasingly becoming optional in adult life now,” said Susan Brown, a professor of sociology at Bowling Green State University in Ohio, who was not involved in the new report.

Nowadays, people expect to be financially secure and to have finished education before they enter marriage, Brown said. “For many people, this is a very high hurdle,” Brown said. The average age for marriage is 26.5 for women and 28.5 for men — an all time high.

However, people are not shunning marriage completely. Over a three-year period of the study, 40 percent of cohabiting couples got married, 32 percent stayed together and 27 percent broke up.

“Even though marriage is being delayed, it's not forgone” said study researcher Casey Copen, a demographer at the CDC's National Center for Health Statistics, which put out the report. Some people cite financial factors, such as wanting to buy a house first, as reasons for delaying marriage, Copen said.

The report also found:

  • The length of time people live together before marriage is increasing, from 13 months in 1995 to 22 months in the 2006 to 2010 survey.
  • White women and those with a higher education were more likely to get married during the study period, compared with Hispanic and black women, and those with less education. For instance, 53 percent of women with a bachelor's degree or higher got married over a three year period, compared to 30 percent of those with less than a high school diploma.
  • Nearly one in five women (19 percent) became pregnant within the first year of cohabitation.
  • Fewer cohabiting women now get married soon after becoming pregnant — in the 2006 to 2010 survey, 19 percent of cohabiting women got married within 6 months of becoming pregnant, compared to 32 percent in 1995.

The findings are inline with a previous survey by the CDC that found that births to cohabiting couples make up nearly half of all births that occur outside of marriage.

Research suggests that children of cohabiting couples don't do as well as those of married couples in terms of education and health, but these disparities have been attributed to the instability and financial struggles of couples, rather than their status as cohabiting, said Corinne Reczek, an assistant professor in the department of sociology at the University of Cincinnati.

“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.”

Pass it on: An increasing number of couples cohabit before marriage.

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