Unmarried Cohabitation and Family Formation in Japan

James Raymo, University of Wisconsin at Madison
Miho Iwasawa, National Institute of Population and Social Security Research, Tokyo

Recent studies have documented a rapid increase in nonmarital cohabitation in Japan. In this paper, we use nationally representative data to examine the relationship between cohabitation experience and the transition to marriage and parenthood among Japanese women. Using the results of discrete-time hazard models to construct synthetic cohort trajectories, we compare the transition to first marriage and first birth among women who have lived in a cohabiting union with those who have not. Cumulative marriage trajectories indicate that (a) cohabitation experience is not strongly associated with marriage timing and (b) differences in the transition to marriage at early ages likely reflect a higher incidence of premarital pregnancy among women who have ever cohabited. Cumulative first birth trajectories suggest that nonmarital unions are heterogeneous, with cohabitation experience associated with a faster transition to parenthood through age 27 and a slower transition to parenthood thereafter.