The most incisive guide to issues facing the American family today . . . An invaluable resource for anyone wishing to stay on the cutting edge of research on family trends.

-W. Bradford Wilcox
Associate Professor of Sociology, University of Virginia 

Preventing Teenage Cohabitation

Bryce J. Christensen and Nicole M. King

Cohabitation may be the norm for couples in their 20s and beyond who are “testing the waters” of marriage, or just choosing to forego the sacred institution altogether, but sociologists still see the practice as detrimental to teens. So it is of great interest when researchers take a close look at what factors influence a teen’s decision to leave the nest and move in with a significant other. And Rena Cornell Zito from Westminster College has found that family background plays an important role in teens’ likelihood of cohabitation.

Zito begins her study by outlining that although “[c]ohabitation has become a normative part of adult relationship trajectories . . . it is considered an off-time transition among teenagers with negative consequences for life-course outcomes, including relationship conflict and unplanned, nonmarital pregnancies.” Other studies have traced a link between teenage cohabitation and living with a single mother or stepfamilies, but Zito believes that the larger, more complicated issues of family structure and parenting have not been explored. She posits an “instability model” that would test the links between teenage cohabitation and family structure instability, economic disadvantage, peer networks, and poor parenting (characterized by weak parental bonds and lax oversight of children).

Zito hypothesizes that “high levels of instability mediate the effects of family structure experiences (i.e., single motherhood, cohabitation, and stepfamilies) on early cohabitation, with altered conditions of childrearing—maternal well-being, maternal bonds, parental control—mediating the influence of instability on exposure to deviant peers and teenage dating, which ultimately predict teenage cohabitation.” In other words, it is not family structure per se which makes a teen more likely to cohabit, but the instability, weakened parental bonds, poverty, and features attending family structure.

To test this theory, Zito pools data from three waves of a nationally representative survey of adolescents who were in middle and high school in 1994-1995. The dependent variable is cohabitation, defined as “if they had ever lived with someone in a marriage-like relationship for more than 1 month” by age 19. The independent variables are family structure history, frequency of structure transitions, and maternal dating; family process mechanisms, which takes into account such variables as maternal happiness, maternal bonds, and parental control over teens’ activities; peer contexts, including how often peers “smoked, got drunk, lied to parents, and skipped school”; and family and neighborhood disadvantage, measuring “family poverty,” “neighborhood economic disadvantage,” and “neighborhood family disadvantage”—i.e., the family instability of those in the teens’ neighborhood. Zito also controls for a number of variables: race/ethnicity, age, maternal age and birth, and maternal education. 

Zito finds that while family structure at birth is “nonsignificant,” “more proximate family structure matters: the odds of teenage cohabitation are 67.0% higher among adolescents in single-mother families relative to adolescents in married, biological-parent families; the odds are 59.5% higher among those in stepfamilies.” In addition, “living below the poverty line” and “[n]eighborhood family disadvantage (i.e., high proportion of female-headed households and single men)” both increase the risk of teenage cohabitation. 

In the third model, the data reveal that instability in and of itself doesn’t seem to amount to much, as the frequency of family structure transitions does not reach statistical significance, although it does moderate the effects of living with a stepfamily. Zito pronounces that “the instability hypothesis is not supported generally, except with regard to mediational processes.” Eager to prove her point, however, Zito then argues for an alternative method of testing the effects of instability, by looking at “the role of family structure among adolescents from stable households (i.e., families with no transitions. The results from this analysis indicate no effect of single motherhood or maternal cohabitation on teenage cohabitation among adolescents in stable households.” 

Lastly, Zito looks at family process mechanisms and deviant peer networks. Not surprisingly, close maternal bonds (unless the mother herself is cohabiting) and careful parental control over teens’ daily activities both lower the odds of teenage cohabitation. Also not surprising is that being in a deviant peer network increases teens’ odds of cohabiting, as does teen dating.  

Zito concludes by summarizing her findings, most notably that “adolescents with histories of single motherhood and stepfamily living are particularly likely to cohabit, in part because of instability, family poverty, residence in neighborhoods marked by family disruption, and weakened maternal bonds.” She also cheerfully reports that “[s]ingle motherhood is irrelevant when predicting teenage cohabitation among adolescents from stable homes,” while admitting that “instability fails to predict teenage cohabitation when controlling for family structure in the main model even though instability mediates much of the stepfamily effect.”

“A second contribution” of her study, Zito believes, is “its treatment of neighborhood economy- and family-based disadvantage as distinct influences.” More specifically, it is surprising to Zito that although neighborhood family disadvantage is significant in predicting teen cohabitation, neighborhood economic disadvantage is not: “The failure of economic disadvantage to predict teenage cohabitation suggests that it is instead community norms regarding appropriate family living that guide patterns of teenage cohabitation.” Once marriages begin to fail in a community, in other words, the moral fabric of that community is weakened.

Zito closes by outlining directions for future research, and claiming partial support for the instability model. Her research is useful, for it emphasizes the precise ways in which family instability, poverty, neighborhood poverty and family structure, and peer networks interact to encourage or discourage teenage cohabitation. Nonetheless, perhaps most notable is what the instability model fails to prove: that instability largely predicts teenage cohabitation. 

In the end, it is clear that there is something about the two-parent, married family that in and of itself protects teens from the perils of shacking up, and something about all other family forms that fail to offer this protection.

(Rena Cornell Zito, “Family Structure History and Teenage Cohabitation: Instability, Socioeconomic Disadvantage, or Transmission?” Journal of Family Issues 36.3 [2015]: 299-325.)