Using UK birth cohorts (1940–1989), Alessandro Di Nallo shows that parental occupational class predicts whether first births occur in marriage, cohabitation, or while single – and at what ages. Despite the rise of cohabitation, class gaps persist: lower-class backgrounds are linked to earlier childbearing and more frequent nonmarital births.
First births set the pace of adult life. Whether people have their first child while married, cohabiting, or single is closely tied to economic security, housing, childcare needs, and how families weather shocks. In Britain, cohabitation has become common, but not everyone follows the same path. A key, often overlooked, piece of the story is parents’ social class, i.e. the socioeconomic background they grow up in.
What the UK data show
In a recent paper (Di Nallo 2025), drawing on nationally representative longitudinal data for people born between 1940 and 1989, I examined how parental occupational class relates to the timing and context of first births.
Three clear patterns emerged. First, there are different roads to parenthood by class. Adults with parents in lower occupational classes are more likely to have their first child earlier and outside marriage – in cohabitation or, less often, while single (Figure 1). Those with parents in higher classes tend to postpone and are more likely to have their first child within marriage. These gaps remain visible even as cohabitation has spread.
Second, cohorts move but the gradient tends to persist. Across birth cohorts, cohabiting first births increase and marital first births shift to later ages. Yet the class gradient doesn’t vanish: nonmarital first births remain more concentrated among those from less advantaged backgrounds, while marital first births remain more common among the better-off (Figure 2).
Third, age matters, albeit differently by background. Among those with parents from lower classes, first births cluster at younger ages across union types. Among those from higher classes, first births peak later, especially within marriage. These age profiles underscore how early family formation can intersect with education and work trajectories.
A breakdown by gender, which can be found find in my article’s appendix, suggests that the link between parents’ class and first-birth context may be somewhat stronger for women than for men, but this exploratory evidence was not formally tested (and was not the paper’s primary focus).
What this means
Family change has not erased social inequality: it has merely rearranged it. With the increase in cohabitation, class differences have shifted away from a simple married–unmarried divide. They are now reflected in who cohabits, who marries, and when. The implications are practical: earlier and nonmarital first births often coincide with tighter budgets, less stable housing, and greater childcare constraints, making access to affordable childcare, housing support, and secure work especially salient for families starting out outside marriage. At the same time, delayed childbirth and later marriage among the better-off highlights the role of education and early-career stability in shaping when and how people form families.
References
Di Nallo, A. (2025) The partnership context of first parenthood – and how it varies by parental class and birth cohort in the United Kingdom. Demographic Research 53(16): 465–510.
Koops, J.C., Liefbroer, A.C., and Gauthier, A.H., (2017). The influence of parental educational attainment on the partnership context at first birth in 16 Western societies. European Journal of Population 33(4): 533–557. doi:10.1007/s10680-017-9421-9.
McLanahan, S. (2004). Diverging destinies: How children are faring under the Second Demographic Transition. Demography 41(4): 607–627. doi:10.1353/dem.2004.0033.
Ní Bhrolcháin, M. and Beaujouan, É. (2013). Education and cohabitation in Britain: A return to traditional patterns? Population and Development Review 39(3): 441–458. doi:10.1111/j.1728-4457.2013.00611.x.