The role of premarital cohabitation in the timing of first birth in China

Background: Premarital cohabitation has become an increasingly popular pathway to marriage in China. However, we lack studies on its role in the timing of first birth. Objective: Motivated by the “second demographic transition” (SDT) theory, three questions are examined: (1) Does cohabitation accelerate the timing of first birth via premarital conceptions? (2) Are cohabitants who are not pregnant at the time of marriage more likely to delay parenthood than non-cohabitants? (3) Does the association between premarital cohabitation and the timing of first birth vary by birth cohort? Methods: Information regarding premarital cohabitational experience and age (in months) at first birth was collected from 7,310 women in the 2010–2018 China Family Panel Studies (CFPS). The role of cohabitation in the timing of first birth was evaluated using a discrete time competing-risk model. Results: Premarital cohabitation accelerates the timing of first birth by increasing the risk of premarital conceptions, but it delays first birth conceived within marriage. The fertility-accelerating effect of premarital cohabitation rebounds in the post-1980s generation after a temporary decline between the 1960s and 1970s birth cohorts, while the fertility-delaying effect of cohabitation has been consistently observed without any sign of decline or rebound over time. Conclusions: The contradictory role of premarital cohabitation in the timing of first birth in China exemplifies a complex interplay between the tendency for path dependency and nonconformist value reorientations in the SDT. The rebound of the fertility-accelerating effect of cohabitation among the post-1980s generation suggests that the two contradictory roles of cohabitation will likely coexist for a long time. Contribution: The fertility-delaying effect of premarital cohabitation is largely compensated for by the fertility-accelerating effect of cohabitation. A cohabitant-noncohabitant gap in the probability of being childless by age 30 emerges when the fertility-delaying effect of cohabitation is exacerbated by a considerable delay in marriage.