Shifting Influences of Pregnancy on Union Formation Across Age and Union Stability Across Cohabitation Duration

Nonmarital pregnancy increases the likelihood of entering a marital or cohabiting union. The timing of a pregnancy within the life course of an individual or relationship duration may also affect the likelihood of forming coresidential unions and their stability. This study examines the association between nonmarital pregnancy and first union formation and how this varies across age. It also considers whether the influence of pregnancy on the stability of cohabitations shifts across their duration. Using data on young adults in the United States (Add Health), competing-risk event-history models examine the time-varying influence of pregnancy on union formation and stability. Findings suggest that pregnancy is more strongly associated with union formation during adolescence, becoming less influential as women age. Within cohabitations, pregnancy had a bigger impact on increasing the likelihood of marriage early within unions, but the longer a couple cohabited the less likely they were to transition to marriage when pregnant