Changes in the Relationship between the Outcomes of Cohabiting Partnerships and Fertility in Britain: Evidence from the 1958 and 1970 Birth Cohort Studies

Fiona Steele, University of London
Constantinos Kallis, University of London
Harvey Goldstein, University of London
Heather Joshi, University of London

We investigate the relationship between the presence and characteristics of children and the outcomes of nonmarital unions among two cohorts of British women. We compare the effect of having children on the risk of partnership dissolution and on the odds that cohabitation is converted to marriage for women born in 1958 and 1970. The analysis uses a multilevel competing risks model to allow for multiple partnerships and births, and to distinguish between two outcomes of cohabiting unions (separation and marriage). We also use a multiprocess model, in which the outcomes of cohabitation are modeled simultaneously with fertility, to allow for the potential joint determination of partnership and childbearing decisions. The analysis is based on partnership and birth histories between the ages of 16 and 30 from the National Child Development Study and the 1970 British Birth Cohort Study.