The new dynamics of family formation and the explosion of childbearing outside marriage

Publication type

Book Chapter

Series Number



Women and Employment: Changing Lives and New Challenges


Publication date

June 1, 2008


After 1975, when the contraceptive pill became freely available to all women, childbearing outside marriage began to increase rapidly after decades of relative stability, reaching 42 per cent in 2004. This was partly driven by a steep increase in age-specific non-marital births rates among women aged 20-34 from the mid-1970s to the early 1990s, after which they stabilised at a high level. At fixed average non-marital and marital age-specific birth rates, this increase in the proportion of births outside marriage can be mainly accounted for by a large fall in the proportion of women aged 20-34 who are married, which is in turn associated with a dramatic rise in cohabiting unions. These unions are short-lived before either dissolving or being converted into marriage. But this begs the question: why didn’t average non-marital fertility rates fall when more women cohabited? Women had the means (reliable contraception and legal abortion) to avoid non-marital childbearing if they wanted to do so, and so the substitution of cohabiting unions for marriages need not have raised non-marital fertility.
A theory of marriage market search (courtship) in which out-of-wedlock childbearing is an option suggests why it may be a rational choice, even when fertility can be controlled. A woman’s well-being as an unmarried mother is likely to be influenced by the prevalence of unmarried mothers in the population. When their prevalence is low, non-marital childbearing is discouraged, because of social stigma against them. A temporary change in the determinants of non-marital childbearing that raises it, like the large rise in unemployment in the in the first half of the 1980s, can produce rapid erosion of the stigma and a self-reinforcing rise in childbearing outside marriage. This dynamic is likely to be concentrated among a segment of the population who already has stronger incentives to have a child before marriage, such as women with low levels of education. The evidence indeed indicates that the chances of having a child before marriage increased by much more among women with low levels of education. An alternative, or complementary, explanation stresses the role of the rise in cohabiting unions and delay in partnership. These generated an increase in non-marital births by increasing the unmarried population. This view also points to the operation of a social influence model in explaining the dramatic rise in cohabitation, and the chapter provides evidence consistent with a diffusion of cohabiting unions from the better educated to the less educated population.


Volume: 133-155



by Jacqueline Scott, Shirley Dex and Heather Joshi (eds)



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