EARLY SEXUAL BEHAVIOR AND FIRST UNION FORMATION IN YOUNG ADULTS By

ii Using the first six rounds of data from the 1997 National Longitudinal Survey of Youth, I analyze the role of sexual behavior on union formation for 6,700 young adults (ages 18 to 22). I investigate whether early sexual activity influences the likelihood of experiencing a co-residential union in early adulthood and whether it is marriage or cohabitation. Results show that earlier ages at first sex and more sexual partners increase the likelihood of experiencing a cohabiting first co-residential union. Sexually active adolescents are less likely to marry or remain single than their counterparts who delayed first sex and had fewer sexual partners. These findings suggest that individuals who enter early cohabiting first unions have different sexual behavior than those who enter early marriages or stay single. Cohabitation has emerged as an alternative union to marriage in which individuals ’ early sexual behavior influences the kind of first union they first experience