Research showed that young adult women whose mothers reported cohabitation were 57 percent more likely than other women to report cohabitation themselves. In addition, daughters of cohabiting mothers tended to cohabit at earlier ages than others.
"Women tend to model the behavior of their mothers when it comes to relationships," said Leanna Mellott, co-author of the study and a graduate student in sociology at Ohio State University .
The likelihood that sons would cohabit was not affected by whether their mothers lived with a man outside marriage, but there were other effects: sons were more likely to cohabit if their mothers were divorced or had their first child at an early age.
While there has been a lot of research on how divorce affects children, this is one of few studies on the impact of cohabitation, said Zhenchao Qian, another co-author and associate professor of sociology at Ohio State .
More than one-third of all births in the United States in 2003 were to unmarried women.
"As more people enter into cohabiting relationships and have children, we have to recognize that this could have long-term effects on these children as they enter adulthood," Qian said.
Mellott presented the team's findings Aug. 16 in Philadelphia at the annual meeting of the American Sociological Association. Mellott and Qian conducted the study with Daniel Lichter, a former Ohio State professor now at Cornell University .
Data for the study came from the National Longitudinal Survey of Youth, a nationally representative survey of people nationwide conducted by Ohio State 's Center for Human Resource Research. Men and women aged 14 to 22 in 1979 were interviewed annually from 1979 to 1994, and once every two years from 1996 forward. The NLSY also interviewed these participants' children.
This study included data on women in the NLSY who had children who were at least 18 years old by 2000. There were 2,426 of these young adults in this study.
Mellott said that the mothers in this study were not representative of all mothers, because they had children at a relatively young age. In addition, this NLSY sample includes more minorities than the general population.
Still, the researchers noted that the strong effects of cohabitation on adult children were consistent, even after taking into account factors such as race, education, and poverty, which all have their own strong links to cohabitation.
Other results of the study showed that young Black men were about 35 percent less likely than white men to report cohabitation, while Black women were 90 percent less likely to have cohabited than their white counterparts.
Education was another important factor, with higher levels of schooling consistently linked to lower levels of living together outside of marriage.
While religion itself was not linked to cohabitation, people who attended religious services weekly were much less likely to live together than those who attended rarely or never.
Young adults' relationships were also affected by the stability of their mothers' relationships, the study showed.
Each relationship transition for the mothers - including divorce, widowhood or new cohabitation -- increased the likelihood of cohabitation by 32 percent for their sons, and 42 percent for their daughters.
Mellott described this study as just the first step in trying to determine how living together outside marriage may affect children who grow up in such an environment.
"We need to further study both the number and type of relationship transitions - such as divorce or cohabiting - for mothers and their children," she said.
"There's been much discussion in society about healthy marriages and how to promote them, but we really need to know more about how these concepts are passed from generation to generation."
This study was supported in part by a grant from the National Institute of Child Health and Human Development.
Contact: Leanna Mellott, (614) 688-5835; Mellott.firstname.lastname@example.org
Zhenchao Qian, (614) 688-8612; Qian.email@example.com
Written by Jeff Grabmeier, (614) 292-8457; Grabmeier.firstname.lastname@example.org