The Formation of Same-Sex and Different-Sex Unions During Young Adulthood: Evidence from Two British Birth Cohorts

PWP-CCPR-2012-001

Abstract

Legal recognition of same-sex relationships is intensely debated, but there is little research about the
formation of same-sex unions. In this paper, I describe the sequencing, timing, and correlates of entering
same-sex and different-sex unions using data from two British birth cohorts, the National Child
Development Study (NCDS) and the 1970 British Birth Cohort Study (BCS). The NCDS and BCS are
unique sources of data because they contain retrospective data from young adults (age 16-34) about samesex cohabiting unions since 1974. The results show that individuals usually have either male or female
partners (rather than both male and female partners). Individuals enter same-sex unions later in young
adulthood than they enter different-sex cohabitation or marriage. Young adults from later birth cohorts,
more socially liberal regions, and high-skilled occupations are more likely to enter same-sex unions. This
paper contributes to the emerging body of research on same-sex unions and sociological theory about
union formation and the relationship market.